A Saudi citizen accused of covertly placing a listening device in an OpenAI meeting room received what US prosecutors described as “substantial support” from the Saudi government, according to a court document filed in California.

Prosecutors said Abdulrahman Alfozan, an employee of the company behind ChatGPT, had been in regular contact with a member of Saudi Arabia’s royal family. They also alleged that a Saudi military official paid for a one-way ticket to Saudi Arabia for his wife and child following his arrest.

The 35-year-old engineer was considered a potential flight risk and was refused bail on Monday while he awaits trial.

Saudi authorities did not reply to requests for comment.

Alfozan had reportedly worked for OpenAI for about a year before the alleged attempt to install the recording equipment.

The company found the device on 30 September. It had been connected behind a television in a conference room and concealed with toilet paper.

A camera was then installed in the room. On 5 October, footage allegedly showed Alfozan entering the space and appearing to inspect the area behind the television where the recorder had been hidden.

FBI agents arrested him on 9 October, and OpenAI ended his employment contract.

The filing said the alleged actions could present “a danger to the national security of the United States”, as company executives had met government representatives in that room during the period when the device was believed to be active.

It also stated that Alfozan was arrested three days before he was due to leave San Francisco for Riyadh on a one-way flight with his wife and son.

After the arrest, prosecutors said his wife told FBI agents that her US visa was nearing expiration and that she and her son were relocating permanently to Saudi Arabia. She reportedly said Alfozan intended to return as well.

On 10 October, one day after his arrest, his wife and son travelled from San Francisco to Doha, Qatar. Their one-way business-class journey was reportedly arranged and paid for by a Saudi military official.

“Ultimately, the defendant has little incentive to remain in the United States to see this case through,” prosecutors said.

US District Judge Alex Tse denied Alfozan’s request for release on bail on Monday, concluding that there was “a significant risk” that he would fail to appear.

The FBI investigation remains under way.

Alfozan was due to appear in federal court in San Francisco later on Monday. If found guilty, he could face up to five years in prison and a fine of $250,000 (£188,000).